Induction of abnormal proliferation by nonmyelinating schwann cells triggers neurofibroma formation.

Recent evidence suggests that alterations in the self-renewal program of stem/progenitor cells can cause tumorigenesis. By utilizing genetically engineered mouse models of neurofibromatosis type 1 (NF1), we demonstrated that plexiform neurofibroma, the only benign peripheral nerve sheath tumor with potential for malignant transformation, results from Nf1 deficiency in fetal stem/progenitor cells of peripheral nerves. Surprisingly, this did not cause hyperproliferation or tumorigenesis in early postnatal period. Instead, peripheral nerve development appeared largely normal in the absence of Nf1 except for abnormal Remak bundles, the nonmyelinated axon-Schwann cell unit, identified in postnatal mutant nerves. Subsequent degeneration of abnormal Remak bundles was accompanied by initial expansion of nonmyelinating Schwann cells. We suggest abnormally differentiated Remak bundles as a cell of origin for plexiform neurofibroma.

Ginger-partitioned moxibustion in prevention of vomiting induced by chemotherapy in advanced malignant bone tumors: a randomized controlled trial / 中国针灸

OBJECTIVE@#To observe the effect of ginger-partitioned moxibustion on digestive tract reaction, quality of life and white blood cell count after chemotherapy in advanced malignant bone tumors patients.@*METHODS@#A total of 64 patients were randomly divided into an observation group and a control group, 32 cases in each group. Both groups were treated with adriamycin combined with cisplatin (AP) chemotherapy. The patients in the control group were treated by tropisetron hydrochloride intravenous on preventing the vomiting 1 h before receiving chemotherapy. On the basis of the control group, the patients in the observation group were treated with ginger-partitioned moxibustion at Neiguan (PC 6), Zusanli (ST 36), Shenque (CV 8), and Zhongwan (CV 12) 2 h after chemotherapy, once a day, 30 min each time. The course of chemotherapy, ginger-partitioned moxibustion and tropisetron hydrochloride intravenous was 5 days. The digestive tract reaction rating, quality of life score and white blood cell count were compared 1 d before chemotherapy, 2 d after chemotherapy and 7 d after chemotherapy between the two groups.@*RESULTS@#The number of 0 grade in digestive tract reaction 2 d and 7 d after chemotherapy in the observation group was significantly higher than that in the control group (@*CONCLUSION@#Ginger-partitioned moxibustion can prevent and treat vomiting after chemotherapy in advanced malignant bone tumors, and improve the quality of life and white blood cell count of patients.

Preliminary evaluation of tear production in dogs hospitalized in an intensive care unit.

OBJECTIVE: To determine the tear production in dogs admitted to an intensive care unit (ICU). DESIGN: Prospective observational study from November 2010-September 2011. SETTING: Private emergency and referral hospital. ANIMALS: Thirty healthy control dogs and 30 dogs hospitalized in an ICU for treatment of systemic illness without previously diagnosed ophthalmic disorders and no recent history of anesthesia. Enrollment was based on availability of the ophthalmologist within 24 hours of admission to the ICU. INTERVENTIONS: Tear production was measured utilizing Schirmer tear test strips (STT) in healthy control animals as well as in hospitalized canine patients. All patients received an ophthalmic examination by a board-certified veterinary ophthalmologist within 24 hours of admission to the ICU. Lubrication with artificial tear gel every 2-4 hours as needed was implemented after STT was measured. MEASUREMENTS AND MAIN RESULTS: Average tear productions in the control and canine ICU populations were 24.5 mm/min and 13.2 mm/min, respectively. This was found to be statistically significant (P < 0.001). Furthermore, there was a trend toward a decrease in tear production in patients with kidney disease and a trend toward normal tear production in patients with cardiac disease but the sample size was likely too small to enable detection of a statistically significant difference. CONCLUSIONS: This study demonstrates a decrease in tear production in canine ICU patients. While further study is warranted to determine how different diseases impact tear production, these finding support the implementation of frequent ocular lubrication in all ICU patients.

Influence of hormones and hormone metabolites on the growth of Schwann cells derived from embryonic stem cells and on tumor cell lines expressing variable levels of neurofibromin.

Loss of neurofibromin, the protein product of the tumor suppressor gene neurofibromatosis type 1 (NF1), is associated with neurofibromas, composed largely of Schwann cells. The number and size of neurofibromas in NF1 patients have been shown to increase during pregnancy. A mouse embryonic stem cell (mESC) model was used, in which mESCs with varying levels of neurofibromin were differentiated into Schwann-like cells. NF1 cell lines derived from a malignant and a benign human tumor were used to study proliferation in response to hormones. Estrogen and androgen receptors were not expressed or expressed at very low levels in the NF1+/+ cells, at low levels in NF1+/-cells, and robust levels in NF1-/-cells. A 17beta-estradiol (E2) metabolite, 2-methoxy estradiol (2ME2) is cytotoxic to the NF1-/- malignant tumor cell line, and inhibits proliferation in the other cell lines. 2ME2 or its derivatives could provide new treatment avenues for NF1 hormone-sensitive tumors at times of greatest hormonal influence.

Genomic sequence and spatiotemporal expression comparison of zebrafish mbx1 and its paralog, mbx2.

The expression of midbrain homeobox-1 (mbx1) defines a discrete region in the vertebrate neural plate that will give rise to the mesencephalon, as well as subregions of the diencephalon and retinal field. Here, we report on the identification and cloning of a second Mbx gene in zebrafish, termed mbx2. Genomic sequence comparison suggests that mbx1 and mbx2 are derived from the duplication of a single putative ancestral gene that is conserved in other vertebrates as a single copy gene. Furthermore, phylogenetic analyses indicate that the mbx genes belong to a novel subgroup of paired-like homeobox genes. Finally, quantitative reverse transcriptase-PCR and whole mount in situ hybridization experiments revealed a pattern of partial spatiotemporal expression divergence between the mbx paralogs that correlates with sequence divergence in noncoding regulatory domains. Our data support a subfunctionalization model that may explain the retention of duplicate mbx genes in teleosts.

Treatment of proximal tibial multi-segment comminuted fractures with closed reduction and less invasive stabilization systems / 中国骨伤

<p><b>OBJECTIVE</b>To explore the clinical effects of closed reduction and less invasive stablization system for the treatment of proximal tibial multi-segment comminuted fractures, and to discuss the influence of LISS on reduction and bone union.</p><p><b>METHODS</b>From 2003.7 to 2007.12, 19 patients with proximal tibial multi-segment comminuted fractures were treated with closed reduction and LISS fixation. Fourteen patients were male, 5 patients were female, ranging in age from 21 to 49 years, with an average of 39.2 years. Fifteen patients were injured with direct violence, 4 indirect violence. The reasons of the injuries were vehicle crashes for 14 cases and falling from high places for 3 cases and falling to the ground for 2 cases. All the patients were followed up postoperatively. Callus formation and bony union were recorded by X-ray.</p><p><b>RESULTS</b>All the patients were followed up for a period averaged 12.2 months (ranged 8 to 21 months). No failure of fixation and nonunion. No deformation of plates and screws occurred in patients,no superficial wound infection. According to the criteria of Merchan, 14 patients got an excellent result, 3 good, and 2 poor.</p><p><b>CONCLUSION</b>Closed reduction and less invasive stabilization systems can provide rigid internal fixation for proximal tibial multi-segment comminuted fractures. The LISS provides stable fixation, a high rate of union, and a low rate of infection for proximal tibial multi-segment comminuted fractures.</p>

Surgical treatment of talar neck fractures / 中国骨伤

<p><b>OBJECTIVE</b>To explore the clinical effect of talar neck fractures treated by open reduction and internal fixation with screws.</p><p><b>METHODS</b>Among 28 cases in the study, 20 cases were males and 8 cases were female. The age ranged from 22 to 72 years with an average of 38 years. Based on the Hawkins classification,there were 6 cases of type I,18 of type I and 4 of type II. They were treated by open reduction and internal fixation with screws.</p><p><b>RESULTS</b>Twenty-eight cases were followed up for 1 to 7 years(mean 2.8 years). The evaluation of the results by Hawkins functional rating scale revealed excellent in 14 cases,good in 9 cases, fair in 3 cases and poor in 2 cases. The excellent and good rate were 83.2%. Osteonecrosis occurred in 5 cases with 3 of type II and 2 of type III fractures. Two of 3 cases with talar displacement were found with osteonecrosis or painful arthritis. The subtalar arthritis occurred in 6 cases, 3 of which were associated with ankle arthritis. Two cases underwent arthrodesis because of painful arthritis of the subtalar joint or osteonecrosis of the talar body. Wound infection and anteromedial skin necrosis of the ankle were not found.</p><p><b>CONCLUSION</b>Treatment of talar neck fractures could obtain satisfactory clinical results through open reduction and internal fixation with screws. Protection of the residual blood supply, anatomically reduction and stable fixation are essential for successful treatment of talar neck fractures.</p>

A new alkaloid from Opuntia vulgaris / 药学学报

<p><b>AIM</b>To study the chemical constituents of the stems of Opuntia vulgaris Mill(Cactaceae).</p><p><b>METHODS</b>The compounds of Opuntia vulgaris were isolated by chromatography of Amberlite Dowex 50 and silica gel, and identified by means of UV, IR, MS, 1D and 2D NMR.</p><p><b>RESULTS</b>Three compounds were isolated and identified as: opuntin B(I), 4-hydroxyproline(II) and tyrosine(III).</p><p><b>CONCLUSION</b>Compound I is a new alkaloid.</p>